use super::*;
use crate::ast::*;
use std::io::Write;
use expect_test::{expect, Expect};

fn gen_test(file: &str, program: &str, expected: Expect) {
    let language = tree_sitter_python::language();
    let mut parser = tree_sitter::Parser::new();
    let _ = parser.set_language(&language);
    let tree = parser.parse(file, None).unwrap();
    let program = ast::Program::new().with_file(program).unwrap();

    let mut output = Vec::new();
    let result;

    {
        let mut ctx = Context::new(language)
            .with_input(file.to_owned())
            .with_tree(tree)
            .with_program(program)
            .with_output_stream(Box::new(&mut output) as Box<dyn io::Write>);

        result = ctx.eval();
    }

    if let Err(e) = result {
        writeln!(output, "{e:?}").unwrap();
    }
    expected.assert_eq(&String::from_utf8(output).unwrap())
}

#[test]
fn bin() {
    let language = tree_sitter_python::language();
    let mut ctx = Context::new(language).with_program(Program::new());
    assert_eq!(
        ctx.eval_expr(&Expr::bin(Expr::int(5), "+", Expr::int(10),)),
        Ok(Value::Integer(15))
    );
    assert_eq!(
        ctx.eval_expr(&Expr::bin(Expr::int(5), "==", Expr::int(10),)),
        Ok(Value::Boolean(false))
    );
    assert_eq!(
        ctx.eval_expr(&Expr::bin(Expr::int(5), "<", Expr::int(10),)),
        Ok(Value::Boolean(true))
    );
    assert_eq!(
        ctx.eval_expr(&Expr::bin(
            Expr::bin(Expr::int(5), "<", Expr::int(10),),
            "&&",
            Expr::false_(),
        )),
        Ok(Value::Boolean(false))
    );
}

#[test]
fn test_evaluate_blocks() {
    let language = tree_sitter_python::language();
    let mut ctx = Context::new(language).with_program(Program::new());
    assert_eq!(
        ctx.eval_block(&Block {
            body: vec![
                Statement::Declaration(Declaration {
                    ty: Type::Integer,
                    name: "a".to_owned(),
                    init: None,
                }),
                Statement::Bare(Expr::bin(Expr::ident("a"), "+=", Expr::int(5),)),
            ]
        }),
        Ok(Value::Unit)
    );
    assert_eq!(
        ctx.lookup(&String::from("a")).unwrap().clone(),
        Variable {
            ty: Type::Integer,
            name: "a".to_owned(),
            value: Value::Integer(5)
        }
    );
}

#[test]
fn test_evaluate_if() {
    let language = tree_sitter_python::language();
    let mut ctx = Context::new(language).with_program(Program::new());
    assert_eq!(
        ctx.eval_block(&Block {
            body: vec![
                Statement::Declaration(Declaration {
                    ty: Type::Integer,
                    name: "a".to_owned(),
                    init: Some(Expr::int(1).boxed()),
                }),
                Statement::Bare(Expr::If(IfExpr {
                    condition: Expr::true_().boxed(),
                    then: Block {
                        body: vec![Statement::Bare(Expr::bin(
                            Expr::Ident("a".to_owned()),
                            "+=",
                            Expr::int(5),
                        ))]
                    },
                    else_: Block {
                        body: vec![Statement::Bare(Expr::bin(
                            Expr::ident("a"),
                            "+=",
                            Expr::int(10),
                        ))]
                    }
                }))
            ]
        }),
        Ok(Value::Unit)
    );
    assert_eq!(
        ctx.lookup(&String::from("a")).unwrap().clone(),
        Variable {
            ty: Type::Integer,
            name: "a".to_owned(),
            value: Value::Integer(6)
        }
    );
}

#[test]
fn test_substring() {
    let language = tree_sitter_python::language();
    let mut ctx = Context::new(language).with_program(Program::new());
    assert_eq!(
        ctx.eval_block(&Block {
            body: vec![
                Statement::Declaration(Declaration {
                    ty: Type::String,
                    name: "a".to_owned(),
                    init: Some(Expr::str("foobar").boxed()),
                }),
                Statement::Declaration(Declaration {
                    ty: Type::String,
                    name: "b".to_owned(),
                    init: Some(
                        Expr::call(
                            "substr",
                            [Expr::Ident("a".to_owned()), Expr::int(0), Expr::int(3),]
                        )
                        .boxed()
                    ),
                }),
            ]
        }),
        Ok(Value::Unit)
    );
    assert_eq!(
        ctx.lookup(&String::from("b")).unwrap().clone(),
        Variable {
            ty: Type::String,
            name: "b".to_owned(),
            value: "foo".into()
        }
    );
}

#[test]
fn test_list() {
    let language = tree_sitter_python::language();
    let mut ctx = Context::new(language).with_program(Program::new());
    assert_eq!(
        ctx.eval_block(&Block {
            body: vec![Statement::Declaration(Declaration {
                ty: Type::List,
                name: "a".to_owned(),
                init: Some(
                    Expr::List(List {
                        items: vec![Expr::int(5)]
                    })
                    .boxed()
                ),
            }),]
        }),
        Ok(Value::Unit)
    );
    assert_eq!(
        ctx.lookup(&String::from("a")).unwrap().clone(),
        Variable {
            ty: Type::List,
            name: "a".to_owned(),
            value: vec![5usize.into()].into(),
        }
    );
}

#[test]
fn list_1() {
    gen_test(
        "",
        "BEGIN {
                list a = [5];
                print(a);
            }
            ",
        expect!["[5]"],
    );
}

#[test]
fn list_2() {
    gen_test(
        "",
        "BEGIN {
                list a = [5, 4, 3];
                print(length(a));
            }
            ",
        expect!["3"],
    );
}

#[test]
fn list_3() {
    gen_test(
        "",
        r#"BEGIN {
                list a = [5, 4, 3];
                print(member(a, 3));
                print(", ");
                print(member(a, 6));
            }
            "#,
        expect!["true, false"],
    );
}

#[test]
fn list_4() {
    gen_test(
        "",
        r#"BEGIN {
                list a = [5];
                println(a);
                push(a, 4);
                println(a);
                push(a, 3);
                println(a);
                pop(a);
                println(a);
                pop(a);
                println(a);
            }
            "#,
        expect![[r#"
                [5]
                [5, 4]
                [5, 4, 3]
                [5, 4]
                [5]
            "#]],
    );
}

#[test]
fn list_5() {
    gen_test(
        "",
        r#"BEGIN {
                list a = [5];
                println(isempty(a));
                pop(a);
                println(isempty(a));
            }
            "#,
        expect![[r#"
                false
                true
            "#]],
    );
}

#[test]
fn string_1() {
    gen_test(
        "",
        r#"BEGIN {
                string a = "Foo";
                println(toupper(a));
                println(tolower(a));
            }
            "#,
        expect![[r#"
            FOO
            foo
        "#]],
    );
}

#[test]
fn string_2() {
    gen_test(
        "",
        r#"BEGIN {
                string a = "foo";
                println(a, " is upper? ", isupper(a));
                println(a, " is lower? ", islower(a));

                string b = "Foo";
                println(b, " is upper? ", isupper(b));
                println(b, " is lower? ", islower(b));

                string c = "FOO";
                println(c, " is upper? ", isupper(c));
                println(c, " is lower? ", islower(c));
            }
            "#,
        expect![[r#"
            foo is upper? false
            foo is lower? true
            Foo is upper? false
            Foo is lower? false
            FOO is upper? true
            FOO is lower? false
        "#]],
    );
}

#[test]
fn string_3() {
    gen_test(
        "",
        r#"BEGIN {
                string a = "foo bar baz";
                println("a[3:5]: `", substr(a, 3, 5), "`");
                println("a[2:9]: `", substr(a, 2, 9), "`");
            }
            "#,
        expect![[r#"
            a[3:5]: ` b`
            a[2:9]: `o bar b`
        "#]],
    );
}

#[test]
fn string_4() {
    gen_test(
        "",
        r#"BEGIN {
                string a = "foo bar baz";
                println("a[9:20]: `", substr(a, 9, 20), "`");
            }
            "#,
        expect![[r#"
            a[9:20]: `InvalidStringSlice { length: 11, start: 9, end: 20 }
        "#]],
    );
}

#[test]
fn node_1() {
    gen_test(
        "def foo(a, b): hello()",
        r#"enter function_definition {
            println(text(node));
            println(text(node.name));
        }"#,
        expect![[r#"
            def foo(a, b): hello()
            foo
        "#]],
    );
}